Aircraft purposefully built to avoid radar detection are characterized by shapes with as few different angles as possible. This results in edges which are parallel to each other even if on opposite sides of the aircraft. It is also desirable to have a fuselage that is blended into the wing where any shapes of small radius can be placed on the upper side, unseen by ground radar. Because of this smooth integration, these aircraft are sometimes referred as “flying wings” and are typically characterized by a swept back wing configuration. An example of such an aircraft is the B-2 bomber.
An aircraft of low radar cross section is devoid of any unnecessary protuberances such as a vertical stabilizer, having its function replaced by control surfaces that increase the drag on one wing or the other only when needed and otherwise lie against the wing to become part of the wing. The advantages of all-wing, tailless aircraft are known. For example, tailless aircraft provide enhanced stealthy operating characteristics due to their inherent low-observable configuration. Moreover, all-wing aircraft provide other benefits such as improved efficiency due to reduced weight and drag and, accordingly, are well suited for use in a wide variety of applications such as in autonomous (unmanned) aircraft where the bulge for a pilot to look out doesn't have to be accommodated.
A disadvantage of the tailless aircraft configuration lies in the absence of an aircraft rudder normally incorporated within the vertical tail section. The rudder is provided in conventional aircraft to create a side to side or yaw moment to the aircraft in flight. Therefore, without a rudder, other means must be provided to impart yaw moment to the tailless aircraft. In addition, it is well known in conventional aircraft to provide ailerons to control roll movement of the aircraft in flight. Typically the rudder works in association with the ailerons on conventional aircraft to counter any adverse yaw during roll. Thus, in the absence of a rudder for the tailless aircraft configuration there is an absence of a means for countering the described adverse yaw.
As such, based upon the foregoing, there exists a need for an improved method and device, which improves aircraft roll control characteristics while countering any adverse yaw characteristics without substantially interfering with the aircraft aerodynamic and radar observability characteristics.